CN104680814A - Safety driving control method through yellow light signal on intersection based on wireless technology - Google Patents

Abstract

The invention discloses a safety driving control method through yellow light signal on an intersection based on a wireless technology. The method comprises the following steps: step 1, detecting the current velocity v of a car and the distance S (v) to a parking line; step 2, transmitting the collected data to a database of a center control computer; step 3, calculating the required distance S, within which the car completely stops at the current velocity v; step 4, generating a corresponding command according to the comparison result of S and S (v); step 5, adjusting the time ty<0> of a yellow light; step 6, transmitting the corresponding command to a vehicle-mounted terminal or a mobile terminal of the corresponding car; step 7, broadcasting driving tips by the vehicle-mounted terminal or the mobile terminal after receiving the command. According to the safety driving control method through the yellow light signal on the intersection based on the wireless technology, an intelligent active reminding technology is adopted to provide timely, accurate and enough guidance information for drivers, safe and efficient transit capacity is realized when the yellow light is turned on, fast, comfortable and safe road efficiency is completely played, and the safety driving control method is suitably popularized and applied to Internet of Vehicles in future.

Description

A kind of crossing steady yellow safe driving control method based on wireless technology

Technical field

The present invention relates to radio communication and traffic signalization technology, particularly relate to a kind of based on wireless technology towards crossing steady yellow safe driving control method.

Background technology

" People's Republic of China's law on road traffic safety implementing regulations ", to steady yellow regulation, at signalized crossing, " when amber light is bright, the vehicle having crossed stop line can continue to pass through." when being meant to that amber light is bright to be opened, represent that the right-of-way in this direction closes to an end, red light will open bright.Steady yellow is the alarm signal that intersection right-of-way carries out substituting, and belongs to a kind of transitional control paces in integrative design intersection scheme.Its objective is and be switched to another signal phase from a signal phase safely to guarantee, enable driving vehicle safety braking after stop line that distance stop line is far away, and ensure that the driving vehicle nearer apart from stop line can pass through crossing, smoothly to reach the object of " warning ramp to stop ".

By the above effect to steady yellow and goal analysis, we to find in regulation the regulation of amber light is rigorous not, except " vehicle having crossed stop line can continue to pass through ", also should comprise and not cross stop line but cannot the vehicle of safety braking after stop line.Explicitly not bright in this point regulation, this causes the use of amber light all the time all to have problems, this kind of meaning that the understanding of many people to amber light contains " finally quickly through ", even the amber light that originally should be warning lamp is used as " accelerating advance notice lamp ", has not only slowed down when distance stop line sees that amber light is bright relatively at a distance and accelerate on the contrary! Said exactly " going through stop light " behavior, often causes pernicious traffic hazard, or it is current to affect crossing, causes very large hidden danger to urban road traffic safety.There are some researches show, in the traffic hazard that China's urban road occurs, have more than 60% to occur in crossing, and the statistics of traffic control department shows that " going through stop light " is one of main cause causing intersection traffic accidents.The existing regulation for steady yellow vehicle pass-through does not consider that vehicle is travelling to time nearer apart from stop line, and the unexpected saltus step of signal lamp becomes amber light bright, then cannot safety braking after stop line, and being unscientific, is also inadequate hommization.

Therefore, be necessary to design a kind of safe driving control method towards crossing steady yellow, induction vehicle opens bright moment safety braking or speed limit by crossing at amber light, improves the travel safety of crossing.

Summary of the invention

The object of the invention is to overcome the shortcoming and defect that existing steady yellow vehicle pass-through specifies, provide a kind of based on wireless technology towards crossing steady yellow safe driving control method.

Object of the present invention is achieved through the following technical solutions:

Based on a crossing steady yellow safe driving control method for wireless technology, comprise the steps:

Step 1, at signalized crossing, when letting pass at the end of corresponding green time to certain entrance driveway vehicle, detecting amber light by pick-up unit and opening each vehicle present speed v in bright moment crossing inlet road surveyed area and the distance S to stop line _(v);

Step 2, the data of collection are sent to center-controlling computer by wireless routing or wire message way, and are saved in the database of center-controlling computer;

Required separation distance S when step 3, described center-controlling computer calculate each vehicle vehicle stops completely under current vehicle speed v;

Step 4, when by each vehicle, under current vehicle speed v, vehicle stops completely required separation distance S and each vehicle to the distance S of stop line _(v)compare, if S > is S _(v), then institute's measuring car can not stop completely in stop line, and center-controlling computer generates corresponding vehicle by instruction, passes through, if S≤S to point out induction vehicle _(v), then institute's measuring car can stop completely in stop line, and center-controlling computer generates corresponding red braking information instruction, to point out induction vehicle parking;

Step 5, described center-controlling computer are according to passing through the time Maximum constraint signal controlling machine of stop line in transitable vehicle to yellow time adjust;

Step 6, described center-controlling computer launch command adapted thereto to the car-mounted terminal of corresponding vehicle or mobile phone terminal by wireless device;

Step 7, described car-mounted terminal or mobile phone terminal are reported after receiving instruction and are driven prompting, make corresponding driving behavior for driver.

Further, in step 1, described pick-up unit is induction type pick-up unit, the definition base computing formula of described surveyed area:

$S_0=v_0(t_0+\frac{t_1}{2})+\frac{V_0^2}{2\mathrm{\&mu;g}}+l,$

Wherein:

S ₀--surveyed area to the ultimate range of stop line,

V ₀--the restriction speed of a motor vehicle in section,

T ₀--in the reaction time that driver brakes at intersection parking, value is 1.3s,

T ₁--docking process damping force increases the time, and value is 0.3s,

μ--coefficient of road adhesion,

G--acceleration of gravity, value is 9.8m/s ²,

L--additional distance, value is 15m,

During actual computation, l changes with the concrete section at place, crossing, and μ affects by factors etc. such as pavement behavior, weather, temperature, and actual value can reference table 1.

Table 1. coefficient of road adhesion reference value

Road surface types	Peak factor	Attachment coefficient
			Face, main line	0.8～0.9	0.75
Wet bituminous pavement	0.5～0.7	0.45～0.60
			Wet mixing earth road surface	0.8	0.7
The tight road surface of crushing by snow	0.2	0.15
			Ice road surface	0.1	0.07

Further, the real time traffic data collected described in step 2 utilizes wireless wifi circulation way to be sent to center-controlling computer.

Further, in step 3, when under current vehicle speed v, vehicle stops completely, required separation distance S is determined by following formula:

$S=v(t_0+\frac{t_1}{2})-\frac{1}{8}\mathrm{\&mu;g}{t}_1^2+\frac{v^2}{2\mathrm{\&mu;g}}.$

Further, in step 4, center-controlling computer generates corresponding vehicle by instruction, specifically comprises to point out the induction step that vehicle passes through:

Step 41, calculating vehicle stop completely in stop line and braking distance is S _(v)time supposition speed of a motor vehicle v ', wherein:

$v^{\&prime;}=\sqrt{2\mathrm{\&mu;g}{S}_{\left(v\right)}};$

Step 41, ask for described supposition speed of a motor vehicle v ' and travel speed limit v with section vehicle _mmean value wherein:

$\stackrel{\&OverBar;}{v}=\frac{v^{\&prime;}+v_m}{2};$

Step 41, when time, the vehicle detection speed of a motor vehicle is relatively slow, and center-controlling computer generates the alert row information command of corresponding yellow, suitably accelerates through to point out this vehicle; When time, detected vehicular velocity is relatively very fast, and center-controlling computer generates corresponding green traffic information, at the uniform velocity passes through to point out this vehicle.

Further, in step 5, described center-controlling computer is according to passing through the time Maximum constraint signal controlling machine of stop line in transitable vehicle to yellow time the step of carrying out adjusting specifically comprises:

Step 51, calculate each vehicle and open the bright transit time T to crossing stop line from amber light;

Step 52, ask for the maximum of T of described transit time T _max;

Step 53, by the maximum of T of transit time T _maxyellow time t initial with crossing _y ⁰compare, if then tackle yellow time and carry out time delay adjustment, to meet current yellow time t _y>=T _max, enable vehicle safety crossing; If then yellow time is not adjusted; If then will carry out shortening adjustment yellow time, to meet current yellow time t _ybe a bit larger tham T _max.

Further, in step 51, described transit time T comprise each vehicle keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _right, wherein:

Left-hand bend vehicle speed is: v ₁=v-Δ v ₁,

Δv ₁＝1.96D ₁+2.2G ₁，

Have according to Newton second law: $v^2-v_1^2=2a(S_{\left(v\right)}-{\mathrm{vt}}_{o1})$

Work as vt ₀₁> S _(v)time,

Work as vt ₀₁< S _(v)time,

Right-hand bend vehicle speed is: v ₂=v-Δ v ₂,

Δv ₂＝1.96D ₂+2.2G ₂，

Work as vt ₀> S _(v)time,

Work as vt ₀< S _(v)time,

Wherein:

T _o1-vehicle opens the bright moment to the reaction time of making corresponding driving behavior from amber light;

V-amber light opens bright moment car speed;

V ₁, v ₂-left and right speed of changing trains or buses after even deceleration;

Δ v ₁, Δ v ₂-average speed decreasing value, calculates as speed of a motor vehicle decreasing value;

D ₁, D ₂-degree of curvature (degree);

G ₁, G ₂the average gradient (%) in-road ramp;

The i-section gradient;

μ-coefficient of road adhesion.

Further, described step 52 specifically comprises:

Step 521, calculate each car keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _maxi=max{T _{straight i}, T _{left i}, T _{right i};

Step 522, calculate the T of each vehicle _maximaximum of T _max=max{T _max1, T _max2..., T _maxn.

Further, in step 6, described wireless device is wireless router.

Compared with prior art, tool has the following advantages and effect in the present invention:

(1) amber light opens the bright moment, the vehicle in signalized crossing surveyed area, when meeting current condition all by crossing, do not meet current condition all by stopping brake.Compare general signal to control, " the going through stop light " of crossing stop line because not braking completely during amber light and being formed can be reduced or be forced to make a dash across the red light phenomenon, reduce the incidence of intersection traffic accidents, the vehicle that can not stop completely is made to pass through crossing, improve the traffic efficiency of crossing, decrease the queue length of stop frequency, stop delay and next cycle.

(2) eliminate the factors such as front truck interference simultaneously, avoid fore-aft vehicle driving behavior inharmonious and cause the phenomenon that knocks into the back to occur, improve the security that intersection vehicles is current.

(3) in the present invention, yellow time becomes with crossing actual traffic situation, improves yellow time utilization factor, decreases lost time, improve security and the robustness of crossing.

(4) real-time information of each vehicle when the present invention opens bright by gathering monitored area, crossing amber light, and analyzing and processing is carried out to information, take into full account the actual traffic situation of each vehicle, more rationalize and hommization than current programme, improve vehicle in the current science of crossing steady yellow with effective.

Accompanying drawing explanation

Fig. 1 is the schematic flow sheet of the embodiment of the present invention.

Fig. 2 is that in the embodiment of the present invention, crossing vehicle flows to schematic diagram.

Fig. 3 is the principle schematic of the embodiment of the present invention.

Fig. 4 is yellow time adjustment schematic flow sheet in the embodiment of the present invention.

Embodiment

Be described in further detail goal of the invention of the present invention below in conjunction with the drawings and specific embodiments, embodiment can not repeat one by one at this, but therefore embodiments of the present invention are not defined in following examples.

In the present embodiment, if inner plane crossing, city entrance driveway is unidirectional three tracks for certain, it is v that crossing limits the speed of a motor vehicle ₀=36km/h, surface friction coefficient μ=0.75, left-hand rotation radius is R ₁=25m, right-hand rotation radius R ₂=10m.The reaction time t of driver ₀=1.3s, brake control power increases stage t ₁=0.3s, amber light opens bright moment localized area 9 cars, as shown in Figure 1, 2.

Based on a crossing steady yellow safe driving control method for wireless technology, comprise step:

Step S1: at signalized crossing, when letting pass at the end of corresponding green time to certain entrance driveway vehicle, detecting amber light by pick-up unit and opening each vehicle present speed v in bright moment crossing inlet road surveyed area and the distance S to stop line _(v), the speed of a motor vehicle v that pick-up unit collects each car in localized area is respectively 28.8km/h, 21.6km/h, 28.8km/h, 28.8km/h, 25.2km/h, 21.6km/h, 36.0km/h, 32.4km/h, 28.8km/h and the distance S with stop line by sequence number 1 ~ 9 _(v)be respectively 1.7m, 3.3m, 4.5m, 9.6m, 10.7m, 12.2m, 16.6m, 21.7m, 22.8m.

Step S2: the vehicle real time traffic data collected by pick-up unit passes to central computer, is saved in the database of central computer,

Send center-controlling computer with the information of vehicles collected by detecting device to by wireless routing or wire message way, and be saved in the database of center-controlling computer.

Required separation distance S when step S3, described center-controlling computer calculate each vehicle vehicle stops completely under current vehicle speed v, wherein $S=v(t_0+\frac{t_1}{2})-\frac{1}{8}\mathrm{\&mu;g}{t}_1^2+\frac{v^2}{2\mathrm{\&mu;g}};$

Step S4, when by each vehicle, under current vehicle speed v, vehicle stops completely required separation distance S and each vehicle to the distance S of stop line _(v)compare, if S > is S _(v), then institute's measuring car can not stop completely in stop line, and center-controlling computer generates corresponding vehicle by instruction, passes through, if S≤S to point out induction vehicle _(v), then institute's measuring car can stop completely in stop line, and center-controlling computer generates corresponding red braking information instruction, to point out induction vehicle parking;

Step S5, described center-controlling computer are according to passing through the time Maximum constraint signal controlling machine of stop line in transitable vehicle to yellow time adjust;

Step S6, described center-controlling computer launch command adapted thereto to the car-mounted terminal of corresponding vehicle or mobile phone terminal by wireless wifi;

Step S7, described car-mounted terminal or mobile phone terminal are reported after receiving instruction and are driven prompting, make corresponding driving behavior for driver.

Further, in step 1, described pick-up unit is induction type pick-up unit, the definition base computing formula of described surveyed area:

$S_0=v_0(t_0+\frac{t_1}{2})+\frac{V_0^2}{2\mathrm{\&mu;g}}+l,$

Wherein:

S ₀--surveyed area to the ultimate range of stop line,

V ₀--the restriction speed of a motor vehicle in section,

T ₀--in the reaction time that driver brakes at intersection parking, value is 1.3s,

T ₁--docking process damping force increases the time, and value is 0.3s,

μ--coefficient of road adhesion,

G--acceleration of gravity, value is 9.8m/s ²,

L--additional distance, value is 15m,

During actual computation, l changes with the concrete section at place, crossing, and μ affects by factors etc. such as pavement behavior, weather, temperature.

Further, the real time traffic data collected described in step 2 utilizes wireless wifi circulation way to be sent to center-controlling computer.

Further, in step 4, center-controlling computer generates corresponding vehicle by instruction, specifically comprises to point out the induction step that vehicle passes through:

Step 41, calculating vehicle stop completely in stop line and braking distance is S _(v)time supposition speed of a motor vehicle v ', wherein:

$v^{\&prime;}=\sqrt{2\mathrm{\&mu;g}{S}_{\left(v\right)}};$

Step 41, ask for described supposition speed of a motor vehicle v ' and travel speed limit v with section vehicle _mmean value wherein:

$\stackrel{\&OverBar;}{v}=\frac{v^{\&prime;}+v_m}{2};$

Step 41, when time, the vehicle detection speed of a motor vehicle is relatively slow, and center-controlling computer generates corresponding yellow pass-through command, suitably accelerates through to point out this vehicle; When time, detected vehicular velocity is relatively very fast, and center-controlling computer generates corresponding green pass-through command, at the uniform velocity passes through to point out this vehicle.

Further, in step 5, described center-controlling computer is according to passing through the time Maximum constraint signal controlling machine of stop line in transitable vehicle to yellow time the step of carrying out adjusting specifically comprises:

Step 51, calculate each vehicle and open the bright transit time T to crossing stop line from amber light;

Step 52, ask for the maximum of T of described transit time T _max;

Step 53, by the maximum of T of transit time T _maxyellow time t initial with crossing _y ⁰compare, if then tackle yellow time and carry out time delay adjustment, to meet current yellow time t _y>=T _max, enable vehicle safety crossing; If then yellow time is not adjusted; If then will carry out shortening adjustment yellow time, to meet current yellow time t _ybe a bit larger tham T _max.

Further, in step 51, described transit time T comprise each vehicle keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _right, wherein:

Left-hand bend vehicle speed is: v ₁=v-Δ v ₁,

Δv ₁＝1.96D ₁+2.2G ₁，

Have according to Newton second law: $v^2-v_1^2=2a(S_{\left(v\right)}-{\mathrm{vt}}_{o1})$

Work as vt ₀₁> S _(v)time,

Work as vt ₀₁< S _(v)time,

Right-hand bend vehicle speed is: v ₂=v-Δ v ₂,

Δv ₂＝1.96D ₂+2.2G ₂，

Work as vt ₀> S _(v)time,

Work as vt ₀< S _(v)time,

Wherein:

T _o1-vehicle opens the bright moment to the reaction time making corresponding driving behavior from amber light;

V-amber light opens bright moment car speed;

V ₁, v ₂-left and right speed of changing trains or buses after even deceleration;

Δ v ₁, Δ v ₂-average speed decreasing value, calculates as speed of a motor vehicle decreasing value;

D ₁, D ₂-degree of curvature (degree);

G ₁, G ₂the average gradient (%) in-road ramp;

The i-section gradient;

μ-coefficient of road adhesion.

Further, described step 52 specifically comprises:

Step 521, calculate each car keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _maxi=max{T _{straight i}, T _{left i}, T _{right i};

Step 522, calculate the T of each vehicle _maximaximum of T _max=max{T _max1, T _max2..., T _maxn.

Further, in step 6, described wireless device is wireless router.

In the present embodiment, as shown in Fig. 2 and table two, can draw:

For vehicle 1:v=28.8km/h, S _(v)=1.7m, S=15.95m.S > S _(v), do not meet the condition of vehicle parking braking, meanwhile, detected vehicular velocity is relatively very fast, and center-controlling computer generates corresponding green traffic information, at the uniform velocity passes through crossing to point out this vehicle;

2) vehicle 2:v=21.0km/h, S _(v)=3.3m, S=11.15m.S > S _(v), do not meet the condition of vehicle parking braking, meanwhile, the vehicle detection speed of a motor vehicle is relatively slow, and center-controlling computer generates corresponding yellow pass-through command, suitably accelerates through crossing to point out this vehicle;

3) vehicle 3:v=28.8km/h, S _(v)=4.5m, S=15.95m.S > S _(v), do not meet the condition of vehicle parking braking, meanwhile, detected vehicular velocity is relatively very fast, and center-controlling computer generates corresponding green traffic information, at the uniform velocity passes through crossing to point out this vehicle;

4) vehicle 4:v=28.8km/h, S _(v)=9.6m, S=15.95m.S > S _(v), do not meet the condition of vehicle parking braking, meanwhile, detected vehicular velocity is relatively very fast, and center-controlling computer generates corresponding green traffic information, at the uniform velocity passes through crossing to point out this vehicle;

5) vehicle 5:v=25.2km/h, S _(v)=10.7m, S=13.48m.S > S _(v), do not meet the condition of vehicle parking braking, meanwhile, detected vehicular velocity is relatively very fast, and center-controlling computer generates corresponding green traffic information, at the uniform velocity passes through crossing to point out this vehicle;

6) vehicle 6:v=21.6km/h, S _(v)=12.2m, S=11.15m.S < S _(v), vehicle can safety braking, generates corresponding red braking instruction, brakes to induce vehicle parking;

7) vehicle 7:v=36km/h, S _(v)=16.6m, S=21.30m.S > S _(v), do not meet the condition of vehicle parking braking, meanwhile, detected vehicular velocity is relatively very fast, and center-controlling computer generates corresponding green traffic information, at the uniform velocity passes through crossing to point out this vehicle;

8) vehicle 8:v=32.4km/h, S _(v)=21.7m, S=18.85m.S < S _(v), meet the condition of vehicle parking braking, generate corresponding red braking instruction, brake to induce vehicle parking.

9) vehicle 9:v=28.8km/h, S _(v)=22.80m, S=15.95m.S < S _(v), meet the condition of vehicle parking braking, generate corresponding red braking instruction, brake to induce vehicle parking.

Table 2 analysis processing result

As shown in Figure 3, in this signal phase, the vehicle 1,3,4,5,7 in surveyed area will according to the green received at the uniform velocity pass-through command at the uniform velocity pass through crossing; Vehicle 2 can according to the yellow pass-through command received, and prompting suitably accelerates through crossing, and vehicle 6,8,9 will receive red braking hint instructions, skidding within yellow time.

Meanwhile, central computer, according to the information of vehicles gathered, carries out analytical calculation to yellow time:

1) vehicle 1 keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _max1=0.22s;

2) vehicle 2 keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _max2=0.54s;

3) vehicle 3 keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _max3=0.57s;

4) vehicle 4 keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _max4=1.20s;

5) vehicle 5 keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _max5=1.59s;

6) vehicle 7 keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _max7=2.00s;

To sum up, this signal phase yellow time T _max=max{T _max1, T _max2, T _max3, T _max4, T _max5, T _max7}=2.00s, desirable t when amber light duration is set in actual crossing _y=2.00s.Yellow time adjustment flow process as shown in Figure 4.

The above embodiment of the present invention is only for example of the present invention is clearly described, and is not the restriction to embodiments of the present invention.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here exhaustive without the need to also giving all embodiments.All any amendments done within the spirit and principles in the present invention, equivalent to replace and improvement etc., within the protection domain that all should be included in the claims in the present invention.

Claims (9)

1., based on a crossing steady yellow safe driving control method for wireless technology, it is characterized in that, comprise the steps:

Step 1, at signalized crossing, when letting pass at the end of corresponding green time to certain entrance driveway vehicle, detecting amber light by pick-up unit and opening each vehicle present speed v in bright moment crossing inlet road surveyed area and the distance S to stop line _(v);

Step 2, the data of collection are sent to center-controlling computer by wireless routing or wire message way;

Required separation distance S when step 3, described center-controlling computer calculate each vehicle vehicle stops completely under current vehicle speed v;

Step 4, when by each vehicle, under current vehicle speed v, vehicle stops completely required separation distance S and each vehicle to the distance S of stop line _(v)compare, if S > is S _(v), then institute's measuring car can not stop completely in stop line, and center-controlling computer generates corresponding vehicle by instruction, passes through, if S≤S to point out induction vehicle _(v), then institute's measuring car can stop completely in stop line, and center-controlling computer generates corresponding red braking information instruction, to point out induction vehicle parking;

Step 5, described center-controlling computer are according to passing through the time Maximum constraint signal controlling machine of stop line in transitable vehicle to yellow time adjust;

Step 6, described center-controlling computer launch command adapted thereto to the car-mounted terminal of corresponding vehicle or mobile phone terminal by wireless device;

Step 7, described car-mounted terminal or mobile phone terminal are reported after receiving instruction and are driven prompting, make corresponding driving behavior for driver.

2. the crossing steady yellow safe driving control method based on wireless technology according to claim 1, is characterized in that:

In step 1, described pick-up unit is induction type pick-up unit, the definition base computing formula of described surveyed area:

$S_0=v_0(t_0+\frac{t_1}{2})+\frac{V_0^2}{2\mathrm{\&mu;g}}+l,$

Wherein:

S ₀--surveyed area to the ultimate range of stop line,

V ₀--the restriction speed of a motor vehicle in section,

T ₀--in the reaction time that driver brakes at intersection parking, value is 1.3s,

T ₁--docking process damping force increases the time, and value is 0.3s,

μ--coefficient of road adhesion,

G--acceleration of gravity, value is 9.8m/s ²,

L--additional distance, value is 15m.

3. the crossing steady yellow safe driving control method based on wireless technology according to claim 1, is characterized in that: the real time traffic data collected described in step 2 utilizes wireless wifi circulation way to be sent to center-controlling computer.

4. the crossing steady yellow safe driving control method based on wireless technology according to claim 1, it is characterized in that, in step 3, when under current vehicle speed v, vehicle stops completely, required separation distance S is determined by following formula:

$S=v(t_0+\frac{t_1}{2})-\frac{1}{8}{\mathrm{\&mu;gt}}_1^2+\frac{v^2}{2\mathrm{\&mu;g}}.$

Required separation distance S when described center-controlling computer calculates examined each vehicle vehicle stops completely under current vehicle speed v, if S > is S _(v), then vehicle is generated by instruction, if S≤S _(v), then the step generating vehicle parking instruction specifically comprises:

Step 303, if S≤S _(v), then institute's measuring car can stop completely in stop line, and center-controlling computer generates red braking information instruction, to point out induction vehicle parking, if S > is S _(v), then institute's measuring car can not stop completely in stop line, and center-controlling computer generates traffic information instruction, passes through to point out induction vehicle.

5. the crossing steady yellow safe driving control method based on wireless technology according to claim 4, it is characterized in that, in step 4, center-controlling computer generates corresponding vehicle by instruction, specifically comprises to point out the induction step that vehicle passes through:

Step 41, calculating vehicle stop completely in stop line and braking distance is S _(v)time supposition speed of a motor vehicle v ', wherein:

$v^{\&prime;}=\sqrt{{2\mathrm{\&mu;gS}}_{\left(v\right)}};$

Step 41, ask for described supposition speed of a motor vehicle v ' and travel speed limit v with section vehicle _mmean value wherein:

$\stackrel{\&OverBar;}{v}=\frac{v^{\&prime;}+v_m}{2};$

Step 41, when time, the vehicle detection speed of a motor vehicle is relatively slow, and center-controlling computer generates the alert row information command of corresponding yellow, suitably accelerates through to point out this vehicle; When time, detected vehicular velocity is relatively very fast, and center-controlling computer generates corresponding green traffic information, at the uniform velocity passes through to point out this vehicle.

6. the crossing steady yellow safe driving control method based on wireless technology according to claim 1, it is characterized in that: in step 5, described center-controlling computer is according to passing through the time Maximum constraint signal controlling machine of stop line in transitable vehicle to yellow time the step of carrying out adjusting specifically comprises:

Step 51, calculate each vehicle and open the bright transit time T to crossing stop line from amber light;

Step 52, ask for the maximum of T of described transit time T _max;

Step 53, by the maximum of T of transit time T _maxyellow time t initial with crossing _y ⁰compare, if then tackle yellow time and carry out time delay adjustment, to meet current yellow time t _y>=T _max, enable vehicle safety crossing; If then yellow time is not adjusted; If then will carry out shortening adjustment yellow time, to meet current yellow time t _ybe a bit larger tham T _max.

7. the crossing steady yellow safe driving control method based on wireless technology according to claim 6, is characterized in that: in step 51, described transit time T comprise each vehicle keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _right, wherein:

Left-hand bend vehicle speed is: v ₁=v-Δ v ₁,

Δv ₁＝1.96D ₁+2.2G ₁，

Have according to Newton second law: $v^2-v_1^2=2a(S_{\left(v\right)}-{\mathrm{vt}}_{o1})$

Work as vt ₀₁> S _(v)time,

Work as vt ₀₁< S _(v)time,

Right-hand bend vehicle speed is: v ₂=v-Δ v ₂,

Δv ₂＝1.96D ₂+2.2G ₂，

Work as vt ₀> S _(v)time,

Work as vt ₀< S _(v)time,

Wherein:

T _o1-vehicle opens the bright moment to the reaction time of making corresponding driving behavior from amber light;

V-amber light opens bright moment car speed;

V ₁, v ₂-left and right speed of changing trains or buses after even deceleration;

Δ v ₁, Δ v ₂-average speed decreasing value, calculates as speed of a motor vehicle decreasing value;

D ₁, D ₂-degree of curvature (degree);

G ₁, G ₂the average gradient (%) in-road ramp;

The i-section gradient;

μ-coefficient of road adhesion.

8. the crossing steady yellow safe driving control method based on wireless technology according to claim 7, it is characterized in that, described step 52 specifically comprises:

Step 521, calculate each car keeping straight on, turn left, in situation of turning right by the time T of stop line _directly, T _left, T _rightmaximum of T _maxi=max{T _{straight i}, T _{left i}, T _{right i};

Step 522, calculate the T of each vehicle _maximaximum of T _max=max{T _max1, T _max2..., T _maxn.

9. the crossing steady yellow safe driving control method based on wireless technology according to claim 1, it is characterized in that: in step 6, described wireless device is wireless router.